The present invention relates to rotary direction indicators for handles, knobs or the like, particularly rotary hand wheels used on power tools.
Rotary wheels and knobs are frequently provided with indicia indicating which direction to rotate the knob to achieve the desired result. For example, a rotary knob on a propane tank may have a raised counterclockwise arrow and the associate word xe2x80x9copenxe2x80x9d on one side of the knob and a clockwise arrow and the word xe2x80x9cclosexe2x80x9d on a diagonally opposite side of the knob in order to provide a visual indication as to which direction the knob should be rotated to achieve the desired result. Likewise, medicine bottles may have written indicia on the top of the bottle cap indicating xe2x80x9cpush and rotate to openxe2x80x9d with a corresponding direction arrow indicating the appropriate direction of rotation.
Many times in power tool applications, a rotary actuator such as a hand wheel or a hand crank will be provided enabling the power tool operator to rotate the rotary element and in turn, cause an associated member to move linearly. An example is a shaper table where an operator may rotate a hand wheel to cause the cutter to move axially upward or downward relative to the shaper table surface. Another example is a table saw where the operator will rotate a hand wheel or other rotary actuators mounted on the front surface of the table saw cabinet and in turn, cause the saw blade to raise or lower relative to the table saw table top surface. In many instances, it is not obvious which way to turn the hand wheel to achieve the desired linear motion of the associated member. Furthermore, from product to product, or manufacturer to manufacturer which way one must turn the hand wheel may vary adding to the uncertainty.
Accordingly, it is an object of the present invention to provide a simple and intuitive rotary direction indicator enabling an operator to visually perceive what direction the associated member will move linearly in response to a rotation of a rotatable element. It is further an object of the present invention to provide a simple rotary direction indicator which does not require language text and can be universally understood with minimal or no instruction.
Accordingly, the rotary direction indicator is provided for use with a rotary element which is visible by a user and which can be rotated to cause an associated member to move linearly. The rotary direction indicator has a generally flat surface extending normal to a central axis of rotation. The indicator body has formed therein a pair of indicating arrows; one corresponding to a clockwise rotation and the other corresponding to a counterclockwise rotation of the indicator about the central axis. The indicating arrows are spaced from and curve about the central axis and have pointed arrow heads which indicate the direction of rotation. One of the arrows is perceived to rise out of the surface of the body while the other arrow is perceived to plunge into the surface of the body providing the user with a visual indication of a correspondence between the rotation of the direction indicator and the linear movement of the associated member. In the preferred embodiment, the direction indicator is associated with a rotary actuator and the arrows are three-dimensional and physically rise out of or plunge into the surface of the rotary direction indicator body.